FIG. 1 is a cross-section of a related art Passive Containment Cooling System (PCCS) 10, such as a PCCS 10 useable in an ESBWR or other type of nuclear power plant. For example, PCCS 10 may be submerged in a coolant source like a PCCS pool inside or near a nuclear reactor containment building. As shown in FIG. 1, PCCS 10 may include an inlet 15 that receives steam, heated water, noncombustible gasses, and/or other energetic fluids that may accumulate in a nuclear reactor containment or other power production environment. For example, inlet 15 may include an opening into a nuclear power plant containment that receives such fluids and delivers the fluids to related art PCCS 10. Inlet 15 flows into an upper manifold 11, which may be a large, voided drum or other fluid-receiving structure. One or more end plates 19 may be bolted to upper manifold 11 to close ends of upper manifold 11 for fluid containment.
Upper manifold 11, in turn, connects to several vertical PCCS tubes 12 below upper manifold 11. Fluid may be distributed in manifold 11 and flow into PCCS tubes 12, under gravity and/or energy from inlet 15. Because PCCS tubes 12 may be submerged in a coolant, like chilled water, the increased surface area of PCCS tubes 12 may cool and/or condense fluid received into PCCS 10. Such cooling and condensation in PCCS tubes 12 may further drive the fluid downward into lower manifold 13. Condensed liquid collecting down into lower manifold 13 may flow out through an outlet 14 of PCCS 10. Additional details of related art PCCS structures are described in co-owned US Patent Publication 2015/0146839 to Marquino et al., the entirety of which is incorporated herein by reference in its entirety.